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251.
The rhino is going extinct due to poaching at a rate which far outstrips current law enforcement or conservation efforts to halt their decline. A critical aspect of counter-poaching failures to date is an inaccurate view of the nature of poaching as a crime. Rather than demand-side efforts, attacking elusive smuggling networks or expensive technical solutions like drones, this article notes how a quasi-military tactical approach of ‘combat tracking’ offers the best way to protect the species. Based on wide ranging interviews and fieldwork across dozens of parks in southern Africa, it demonstrates how the current restricted range of the rhino, and the rarity of skilled poachers, makes a tactical solution the most effective to date.  相似文献   
252.
This article reassesses the foreign policy legacy of George W. Bush in light of the emerging historical record of his administration. We conclude that, whereas Bush’s foreign policy was in widespread disrepute when he left office in 2009, that reputation is likely to improve – perhaps significantly – in the coming years. We identify six particular arguments that lend credence to an emerging ‘Bush revisionism.’ To be clear, we do not necessarily argue that the balance sheet on Bush’s foreign policy was positive, but the arguments presented here are likely to generate a more sympathetic and favorable historical assessment of Bush’s presidency over time.  相似文献   
253.
How do we understand combat effectiveness – soldiers’ performance in battle? Despite the broad consensus that understanding combat effectiveness is important both for scholars and policymakers, there is widespread disagreement about what combat effectiveness is. More specifically, studies of effectiveness tend to focus on either the skill of soldiers in battle, or their will to fight. Yet both skill and will are essential components of an effective fighting force. This article argues that understanding combat effectiveness requires understanding both of these key components of effectiveness. In other words, combat effectiveness requires both the skill and will to engage the enemy in an organized manner. It then demonstrates the usefulness of this conceptualization by applying it to the cases of British, Indian, and Australian forces fighting the Japanese during the Second World War. Only when scholars are talking about the same concept will our understanding of the conditions under which militaries are effective in battle progress. By comparing different units fighting the same opponent under the same material conditions, I demonstrate that units vary both in their combat skill and their will to fight, and that understanding their effectiveness in battle requires analyzing both of these key factors.  相似文献   
254.
The post-civil war agreement phase is vulnerable to credible commitment problems, a lack of government capacity to implement, and/or mutual vulnerability to retribution from violating the agreement. This study’s main contribution is to demonstrate the combined utility of mediation and UN peacekeeping. Mediation builds trust and confidence and works with the parties to design an efficacious agreement conducive to, among other features, tamping down post-agreement violence. Peacekeeping stems violence and facilitates the implementation of the agreement. Agreements that are mediated and followed by UN peacekeeping are expected to be more robust in terms of staving off violence. We report the effects of the mediation–peacekeeping interaction using a method correcting for a common misinterpretation of interaction terms. We test logit and hazard models using a sample of full and partial civil war peace agreements signed between 1975 and 2011. Controlling for agreement design, democracy, and income per capita, the results indicate mediation and its interaction with peacekeeping reduce the probability of renewed/continuing violence and have a positive impact on agreement duration. We also report brief case study evidence from the 1990s peace process in Guatemala.  相似文献   
255.
At the core of waging war and strategy is the creation, control and use of force. This article investigates the volunteer battalions that mobilized in Ukraine during the spring of 2014. It contextualizes the volunteer phenomenon and focuses on the state strategies to establish control over these militias. As ambiguous entities arising from a situation characterized by rapid social change – revolution and war – the volunteer battalions threatened existing hierarchies and questioned state authority. The situation was exacerbated by the war, which deviated from the expectations of Ukrainian combatants and Western military observers alike. The state nevertheless enjoyed a modicum of success in reining in the militias through four strategies of undermining, co-option, incorporation and coercion. While predominantly integrated into a more rigid category of paramilitary forces, the volunteers continue to play a role in both the Ukrainian society and security sector to the unforeseeable future.  相似文献   
256.
基于马尔可夫更新过程的装甲装备使用可用度模型   总被引:1,自引:0,他引:1  
针对在装甲装备使用可用度评估中,采用统计评估法存在统计周期长和不能用于研制阶段的缺点,利用马尔可夫更新过程,建立了考虑工作时间、修复性维修时间、延误时间和预防性维修时间的装甲装备的稳态可用度模型,并进行了示例应用。该模型可以在装备研制阶段,根据装备各项时间参数的分布,来估计装甲装备的使用可用度,可为装备设计、装备维修间隔期规划等提供理论和方法指导。  相似文献   
257.
介绍了“油改气”汽车的概念及分类,从改装工艺、关键零部件质量、监督验审、燃气质量等几个方面详细分析了“油改气”汽车的火灾原因,重点就控制燃气泄漏,提出了完善法规体系、严格监督、驾驶人员自觉履行各项安全规程、提高燃气质量等火灾防范措施。  相似文献   
258.
介绍了煤炭的常见储存形式,通过分析煤炭在露天、半露天、室内等储存形式下的火灾危险性,从煤炭储存场所的安全布置、建筑结构防火、消防设施设置、电气设备的选择、消防安全管理等方面提出了针对性的防治措施。  相似文献   
259.
富氧区域具有极大的火灾危险性,在富氧状态下不仅能使通常不燃或难燃的物品变得易燃,而且还会扩大可燃物的燃烧范围,加快可燃物的燃烧速度。因此,必须充分认识富氧区域的火灾危险性,严格富氧区域操作的安全防范措施,确保富氧区域操作安全。  相似文献   
260.
装备预防性维修的维修级别逻辑决策分析方法   总被引:2,自引:1,他引:1  
针对预防性维修的维修级别没有规范、统一的分析与确定方法的问题,研究了预防性维修的维修级别逻辑决策分析方法。明确了预防性维修的维修级别决策分析的对象是预防性维修工作类型,预防性维修主要有定时维修和状态维修,定时维修分为定时拆修和定时报废2种维修工作类型,状态维修分为状态信息检测、状态识别、状态预测、维修决策、故障诊断和维修实施等维修工作类型。根据维修间隔期、维修能力评估、其它非经济性因素以及经济性分析,分别建立了定时维修和状态维修的维修级别逻辑决策模型。  相似文献   
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